Virtual Desktops: It's All About the Network

Virtual desktops will most certainly lower both capital and operational expenses in the data center, but is it possible that slower response times could eat away at those savings by hampering productivity?

That's one of the key concerns of the top virtualization vendors as they ramp up their desktop offerings in the face of a growing cadre of start-ups looking to gain a foothold while the market is still young. And one of the surest ways to boost thin client responsiveness to local PC levels is by cutting through network congestion.

Exhibit A is VMware's recent tie-up with Sun Microsystems, in which the Virtual Desktop Infrastructure (VDI) will fold in the Sun Ray software and client display technology in a play for WAN-based virtual desktop networks that cater to branch offices and long-distance collaboration. The Sun Ray solution features Sun's Appliance Link Protocol (ALP), designed specifically to reduce latency over congested or low-speed wide area networks.

Citrix and partner Microsoft are bringing their own respective network solutions to their combined desktop platform. Systems can be designed around Microsoft's Remote Desktop Protocol (RDP) or Citrix' Independent Computer Architecture (ICA), both of which are optimized for the XenDesktop approach to desktop virtualization, featuring a core, centralized OS and streamed applications. The company claims its system can be booted up faster than a PC, even over low-bandwidth, high-latency WANs.

Citrix is also adding a new element into the mix in the form of the Branch Repeater component in the Citrix Delivery Center family. The idea is to amplify and retransmit signals to distant locations no matter which device or hypervisor is being used. The system is built on Windows Server, which provides the means to consolidate services like Active Directory, domain name system (DNS) and dynamic host configuration protocol (DHCP).

Citrix is also getting its foot in the door of the nascent desktop-as-a-service (DAAS) market, offering financial backing to start-up Desktone. The company has devised the Virtual-D platform that provides full desktop functionality over public or corporate networks. Citrix recently announced support for the XenServer platform, which would be made available through a web-based interface.

Until these systems get a workout in actual enterprise environments, it will be nearly impossible to gauge their performance relative to traditional PCs. Most legacy networks will likely have to be upgraded in some way to handle the additional traffic of virtual desktops, but those improvements are likely to happen anyway, driven by server virtualization, voice communications and increased data loads in general.

But it will be up to the vendors to prove that going virtual makes for not only a cheaper desktop, but a better one.